A victaulic pipe coupling is used to connect a pair of pipes whose ends are formed with grooves. For instance, U.S. Pat. No. 3,054,629 to Piatek issued Sep. 18, 1962 discloses a pipe coupling which comprises a pair of arcuate coupling segments attached to adjacent ends of a pair of pipes. A sealing gasket is located in the coupling segments for engagement with an external periphery at the end of pipes. Each of the coupling segments has keys on their inner periphery for engagement within the grooves formed in the adjacent pipe ends. Provided on each coupling segment are a pair of pads radially extending at opposite ends thereof and having an aperture for receiving a bolt which tightens the coupling segments. Each end of the keys is provided with a chamfer which engages with a side surface of the groove to draw the pipe ends toward each other as the chamfer is forced into the groove until a radial side surface of the key is brought into holding engagement with the side surface of the groove.
Self-adjusting pipe clamp and coupling shown by U.S. Pat. No. 4,611,839 to Rung, et. al. issued Sep. 16, 1986 comprises a pair of coupling segments each having inclined end surfaces for sliding contact to each other. These end surfaces of the coupling segments are positioned in closely proximal relationship to each other upon initial assembly of the coupling onto a pipe having an external diameter which is a maximum diameter within a range of manufacturing tolerances of the pipe.
However, prior art pipe couplings have a serious defect in that they can not fully prevent longitudinal displacement of the pipes since clearance is formed along the longitudinal axis of the pipes between the key sections and side walls of the grooves formed on the pipes. Also, additional defect is in that excessive tightening force loaded on the coupling by bolt causes damage to the pipes and resilient gasket located between the pipe coupling and outer periphery of the pipe.
It is therefore an object of the present invention to provide a skew pipe coupling capable of preventing longitudinal displacement of the pipes without damage to the pipes and a gasket positioned between arcuate housings and outer periphery of the pipe in firmly securing adjacent pipe ends.
Another object of the present invention is to provide a skew pipe coupling easily assembled for strong joint of pipe ends.
Still another object of the present invention is to provide a skew pipe coupling which has a novel structure wherein a pair of arcuate housings may be skewed in opposite directions by a slight angle around a vertical central axis in order to accomplish firm connection of the pipe ends and prevent axial displacement of the pipe ends without any damage to the pipes and gasket.
A further object of the present invention is to provide a pipe coupling in which a pair of arcuate housings may be skewed around a vertical axis to provide skewed arrangement of each key section in the annular groove of the pipe end.